Journal: Theranostics

Article Title: A Novel Peptide Interfering with proBDNF-Sortilin Interaction Alleviates Chronic Inflammatory Pain

doi: 10.7150/thno.29703

Figure Lengend Snippet: Mapping of proBDNF-sortilin interaction interface. (A) Schematic diagram illustrating the design of human BDNF prodomain variants. Six variants with a series of amino acids deletions were used in this study. V66M, Val66Met; S, Signal peptide (amino acid 1-18); BDNF, mature BDNF (amino acid 129-247); HA, C-terminal HA epitope. (B) Immunoblots of co-immunoprecipitation (Left) or inputs (Right) of sortilin and proBDNF variants obtained with antibody against HA or Myc epitope. IP, Immunoprecipitation; IB, Immunoblot. (C) Left , live fluorescence micrograph of BiFC mapping assay (Yellow) using HEK293T cells with VC155-sortilin (Sort1) and VN155(I152L)-BDNF prodomain variants. Scale bar represents 50 µm. Right , quantification of fluorescence intensity of BiFC assay. P <0.0001, one-way ANOVA. ** P <0.01 versus Fl group; *** P <0.0001 versus Fl group; ## P <0.001 versus variant I; ### P <0.0001 versus variant I group; n.s., non-significant. Values are means ± SEM. n = 100 individual cells from 4 images. (D) Left , representative immunoblots of supernatant and cell lysates of HEK293 cells overexpressing sortilin and BDNF prodomain variants obtained with antibodies against HA. Right , densitometry analyses of secreted BDNF in supernatants, normalized to input in lysates. P <0.001, one-way ANOVA. * P <0.05, versus Fl group; *** P <0.001, versus Fl group; ## P <0.05, versus I group. Values are means ± SEM. n = 4. IB, Immunoblot. (E) BDNF ELISA quantification of supernatant collected from HEK293 cells overexpressing sortilin and BDNF prodomain variants. P <0.0001, one-way ANOVA. * P <0.05; ** P <0.01; *** P <0.001, versus Sort1/Fl group; ## P <0.05, versus Sort1/variant I group. Values are means ± SEM. Each data point represents the average of 3 independent experiments.

Article Snippet: The primary antibodies used included anti-proBDNF antibody (#ANT-006-AG, Alomone Labs Ltd, Jerusalem, Israel), anti-phospho-p44/42 MAPK (Erk1/2) (Thr202/Tyr204) antibody (Cell signalling Technology, Danvers, MA, USA), anti-NeuN antibody (MAB377, EMD Millipore Corporation, Billerica, MA, USA) and anti-sortilin antibody (Abcam, Cambridge, UK).

Techniques: Western Blot, Immunoprecipitation, Fluorescence, Mapping Assay, Bimolecular Fluorescence Complementation Assay, Variant Assay, Enzyme-linked Immunosorbent Assay

Journal: Theranostics

Article Title: A Novel Peptide Interfering with proBDNF-Sortilin Interaction Alleviates Chronic Inflammatory Pain

doi: 10.7150/thno.29703

Figure Lengend Snippet: Construction of a novel peptide targeting proBDNF-sortilin Interaction. (A) Schematic diagram illustrating the design of a series of blocking peptides targeting proBDNF-sortilin interaction interface. Scr-bdnf84-83 (scr), scrambled peptide with permutation of peptide sequence at amino acid 84-93. (B) Immunoblots of co-immunoprecipitation (upper) or reverse co-immunoprecipitation (lower) of sortilin and proBDNF variants in cell lysates overexpressing full-length proBDNF and sortilin followed by peptide incubation obtained with antibodies against HA or Myc. IP, Immunoprecipitation; IB, Immunoblot. (C) Schematic diagram of the design of the Tat-tagged interfering peptide. Scr-bdnf89-98-Tat, Tat-tagged scrambled peptide with permutation of peptide sequence at amino acid 89-98. (D) Live fluorescence micrographs of 5FAM (green) or bright field in rat DRG neuronal cultures before (0 min) and incubated with 5 µM 5FAM-tagged bdnf89-98-Tat (bdnf-Tat) for 2 h. Scale bar represents 150 µm. (E) Fluorescence micrograph of 5FAM (green), sortilin (red) or DAPI (blue) in rat DRG neuronal cultures with peptides pre-treatment for 30 min. Scale bars represent 25 µm. (F) Left , fluorescence micrograph of BiFC assay (yellow) of HEK293T cells overexpressing full-length BDNF and sortilin with vehicle, 10 µM scr-Tat or bdnf-Tat pre-treatment for 30 min. Scale bars represent 25 µm. Right , Determination of the corrected total cell fluorescence (CTCF) of the BiFC signal. P <0.0001 , one-way ANOVA. *** P <0.0001, scr-Tat treatment versus bdnf-Tat treatment. Mean values ± SEM. n = 100 individual cells from 5 images. (G) Effect of 30 min peptide pre-treatment on activity-dependent secretion of BDNF in rat DRG neuronal cultures with high-potassium stimulus using ELISA. P <0.05, one-way ANOVA. * P <0.05, vehicle versus scr-Tat treatment or scr-Tat treatment versus bdnf-Tat treatment. Values are means ± SEM. Each data point represents the average of 3 independent experiments.

Article Snippet: The primary antibodies used included anti-proBDNF antibody (#ANT-006-AG, Alomone Labs Ltd, Jerusalem, Israel), anti-phospho-p44/42 MAPK (Erk1/2) (Thr202/Tyr204) antibody (Cell signalling Technology, Danvers, MA, USA), anti-NeuN antibody (MAB377, EMD Millipore Corporation, Billerica, MA, USA) and anti-sortilin antibody (Abcam, Cambridge, UK).

Techniques: Blocking Assay, Sequencing, Western Blot, Immunoprecipitation, Incubation, Fluorescence, Bimolecular Fluorescence Complementation Assay, Activity Assay, Enzyme-linked Immunosorbent Assay